Time course of Tat-dn-H-Ras incubation as a function of inhibition of ERK 1 and ERK 2 activation.

(A) Human eosinophils were incubated with 100 nM Tat-dn-H-Ras for different time intervals and then stimulated for 7 minutes with 1 nM IL-5. Resultant cell lysates were separated by SDS-PAGE and processed for immunoblot analysis using anti-active ERK 1 and ERK 2 antibodies. (B) Cell lysates from panel A were also probed with anti- ERK 1 and ERK 2 antibodies to demonstrate equivalent masses of protein in all samples. Figure 5 is representative of 3 repetitions of this experiment.